To knot or not? Novel feeding behaviours in moray eels


We report observations of a novel feeding behaviour in the moray eel Gymnothorax favagineus (Bloch & Schneider, 1801) and a previously undocumented application of “knotting” behaviour in G. fimbriatus (Bennett, 1832). Moray eels were filmed by baited remote underwater video systems (BRUVS) at the Scott Reefs, a remote group of atoll-like reefs on the edge of the continental shelf in tropical, northwestern Australia. Two behaviours were observed as the moray eels tried to dislodge food from a bait bag: (1) G. favagineus used its tail as a “paddle” to gain leverage on the bag, and (2) G. fimbriatus tied a knot in its tail in order to extract food from the bag. Our observations suggest that morays have an extensive behavioural repertoire for manipulating and extracting large prey items from the interstices of the reefs where they typically hunt.

This is a preview of subscription content, log in to check access.

Access options

Buy single article

Instant unlimited access to the full article PDF.

US$ 39.95

Price includes VAT for USA

Subscribe to journal

Immediate online access to all issues from 2019. Subscription will auto renew annually.

US$ 99

This is the net price. Taxes to be calculated in checkout.

Fig. 1


  1. Bassett DK, Montgomery JC (2011) Investigating nocturnal fish populations in situ using baited underwater video, with special reference to their olfactory capabilities. J Exp Mar Biol Ecol 409:194–199

  2. Böhlke EB, McCosker JE, Böhlke JE (1989) Fishes of the Western North Atlantic. The Yale Peabody Museum. Yale University, New Haven

  3. Brose U, Jonsson T, Berlow EL et al (2006) Consumer-resource body-size relationships in natural food webs. Ecology 87:2411–2417

  4. Cappo M, Speare P, De’ath G (2004) Comparison of baited remote underwater video stations (BRUVS) and prawn (shrimp) trawls for assessments of fish biodiversity in inter-reefal areas of the Great Barrier Reef Marine Park. J Exp Mar Biol Ecol 302:123–152

  5. Carr MH, Hixon MA (1995) Predation effects on early post-settlement survivorship of coral-reef fishes. Mar Ecol Prog Ser 124:31–42

  6. Ebner B, Clear R, Godschalx S, Beitzel M (2009) In-stream behaviour of threatened fishes and their food organisms based on remote video monitoring. Aquat Ecol 43:569–576

  7. Fox RJ, Bellwood DR (2008) Direct versus indirect methods of quantifying herbivore grazing impact on a coral reef. Mar Biol 154:325–334

  8. Graham NAJ, Purkis SJ, Harris A (2009) Diurnal, land-based predation on shore crabs by moray eels in the Chagos Archipelago. Coral Reefs 28:397

  9. Helfman G (1990) Mode selection and mode switching in foraging animals. In: Slater P, Rosenblatt J, Beer C (eds) Advances in the study of behavior, vol 19. Academic, San Diego, pp 249–290

  10. Helfman GS, Clark JB (1986) Rotational feeding: overcoming gape-limited foraging in anguillid eels. Copeia 1986:679–685

  11. Measey GJ, Herrel A (2006) Rotational feeding in caecilians: putting a spin on the evolution of cranial design. Biol Lett 2:485–487

  12. Mehta RS, Wainwright PC (2007a) Raptorial jaws in the throat help moray eels swallow large prey. Nature 449:79–82

  13. Mehta RS, Wainwright PC (2007b) Biting releases constraints on moray eel feeding kinematics. J Exp Biol 210:495–504

  14. Mehta RS, Ward AB, Alfaro ME, Wainwright PC (2010) Elongation of the body in eels. Integr Comp Biol 1091–1105

  15. Miller TJ (1987) Knotting: a previously undescribed feeding behavior in Muraenid eels. Copeia 4:1055–1057

  16. Miller TJ (1989) Feeding behaviour of Echidna nebulosa, Enchelycore pardalis, and Gymnomuraena zebra (Teleostei: Muraenidae). Copeia 3:662–672

  17. Parrish JD, Norris JE, Callahan MW et al (1986) Piscivory in a coral reef fish community. In: Simonstad CA, Cailliet GM (eds) Contemporary Studies on Fish Feeding: the Proceedings of the Gutshop, 1984. Dev Environ Biol Fish 7:285–298

  18. Santos FB, Castro RMC (2003) Activity, habitat utilization, feeding behaviour and diet of the sand moray Gymnothorax ocellatus (Anguilliformes, Muraenidae) in the South Western Atlantic. Biota Neotrop 3:1–7

  19. Smith DG (2012) A checklist of the moray eels of the world. Zootaxa 3474:1–64

  20. Vail AL, Manica A, Bshary R (2013) Referential gestures in fish collaborative hunting. Nat Commun 4:1765. doi:10.1038/ncomms2781

  21. Weiss HM, Lozano-Álvarez E, Briones-Fourzán P, Negrete-Soto F (2006) Using red light with fixed-site video cameras to study the behavior of the spiny lobster, panulirus argus, and associated animals at night and inside their shelters. Mar Technol Soc J 40:86–95

  22. Zintzen V, Roberts CD, Anderson MJ et al (2011) Hagfish predatory behaviour and slime defence mechanism. Sci Rep 1:1–6

Download references


We would like to thank the Australian Institute of Marine Science for the use of its research vessel, the RV Solander, and for the support of its crew. We also acknowledge the Department of Fisheries, the Department of Parks and Wildlife (DPaW) and the Department of Sustainability, Environment, Water, Population and Communities for arranging permits to conduct research at the Scott Reefs. Experimental protocols were approved by the University of Western Australia’s Animal Ethics Committee (RA3/100/1279, RA3/100/1172), and were carried out in accordance with the approved guidelines.

Author information

Correspondence to Shanta C. Barley.

Additional information

Communicated by R. Thiel

Electronic supplementary material

Below is the link to the electronic supplementary material.

(MP4 207673 kb)

(MP4 43012 kb)


(MP4 207673 kb)


(MP4 43012 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Barley, S.C., Mehta, R.S., Meeuwig, J.J. et al. To knot or not? Novel feeding behaviours in moray eels. Mar Biodiv 46, 703–705 (2016) doi:10.1007/s12526-015-0404-y

Download citation


  • Gymnothorax
  • Feeding
  • Coral reef
  • Knotting
  • Baited remote underwater video systems